Substrates for stretchable electronics and method of manufacture
A bulk substrate for stretchable electronics. The bulk substrate is manufactured with a process that forms a soft-elastic region of the bulk substrate. The soft-elastic region includes a strain capacity of greater than or equal to 25% and a first Young's modulus below 10% of a maximum local modulus of the bulk substrate. The process also forms a stiff-elastic region of the bulk substrate. The stiff-elastic region includes a strain capacity of less than or equal to 5% and a second Young's modulus greater than 10% of the maximum local modulus of the bulk substrate.
1. A method of manufacturing a bulk substrate for stretchable electronics comprising:
dispensing a monomer mixture atop a carrier substrate;
curing a monomer mixture into a polymer film atop a carrier substrate;
patterning the polymer film to cover a first region of the polymer film and expose a second region of the polymer film; and
oxidizing exposed portions of the polymer film to create the bulk substrate, wherein the bulk substrate comprises:
a soft-elastic region comprising an elastic limit of greater than 25% and a first Young's modulus less than 50 MPa; and
a stiff-elastic region comprising an elastic limit of less than 5% and a second Young's modulus greater than 50 MPa; wherein the elastic limit is the yield strength after which the deformations are plastic.
2. The method of claim 1 , wherein oxidizing to create the bulk substrate further comprises forming the soft-elastic region and the stiff-elastic region in a single continuous material.
3. The method of claim 1 , wherein the bulk substrate does not comprise adhered interfaces having spatially controlled regions of variable Young's modulus.
4. The method of claim 1 , comprising fabricating electronic stacks atop the stiff-elastic region of the bulk substrate.
5. The method of claim 1 , wherein oxidizing portions of the polymer film to create the bulk substrate comprises creating the stiff elastic region that extends through an entire thickness of the bulk substrate.
6. The method of claim 1 , wherein oxidizing portions of the polymer film to create the bulk substrate comprises creating the stiff-elastic region comprising a hemispherical shape within the soft-elastic region.